Agendia data reveals impact of MammaPrint on adjuvant treatment decisions in breast cancer patients

Agendia, Inc., a world leader in personalized medicine and molecular cancer diagnostics, has presented new prospective data demonstrating the strong impact of its 70-Gene Breast Cancer Recurrence assay, MammaPrint^®, and the corresponding 80-Gene Molecular Subtyping Assay BluePrint^®, in clinical decision-making for patients with early-stage breast cancer in Germany.

The PRospective study to measure the Impact of MammaPrint on adjuvant treatment in hormone receptor-positive HER2-negative breast cancer patients (PRIMe) study was undertaken by the West German Study Group (WSG). It included 452 patients from 27 centers and evaluated the impact of gene expression-based tests MammaPrint and BluePrint, compared to conventional clinico-pathological factors, in deciding whether or not patients would benefit from, and should therefore be treated with adjuvant chemotherapy.

The results, presented at the San Antonio Breast Cancer Conference last week showed a 28.4% change in patients’ treatment plans, originally based on clinico-pathological factors, as a direct result of the data provided by MammaPrint and BluePrint.

Prof. Nadia Harbeck, MD, PhD, PI of the PRIMe study, Scientific Director of the West German Study Group and chair for Conservative Oncology at the Department for OB&GYN of the University of Munich (LMU), Germany, said:

The discordance between conventional clinico-pathological assessment and the results of gene expression-based tests like MammaPrint is substantial. Our study demonstrated that, in Germany, physicians not only welcomed these tests but showed a strong adherence to the test results, even actively changing their previous treatment plans. The > 90% adherence rate to the MammaPrint results regarding adjuvant treatment decisions demonstrated the confidence of physicians in these gene-expression results.

Bastiaan van der Baan, Chief Clinical and Business Development Officer at Agendia said:

The final analysis of the WSG PRIMe study makes plain the importance of gene expression-based tests like MammaPrint, in giving physicians in Germany, and beyond, the definitive results and the confidence they need to provide the safest and most effective treatment plans for their patients.

As the data shows, the current clinico-pathological approach leaves a significant number of women in an unpleasant situation where they are under or over-treated. We believe strongly that early-stage breast cancer patients and their physicians in Germany should be able to access the benefits of a gold-standard gene-expression test like MammaPrint, to enable individualized treatment based on quantitative, reliable, genomic data.

The clinical performance of MammaPrint and its ability to accurately inform and guide treatment decisions was definitively proven by the publication of the MINDACT trial in the New England Journal of Medicine in August. This unique phase III prospective, randomized, controlled study provides the highest level of clinical evidence to MammaPrint (Level 1A), above any other genomic assay, for making adjuvant chemotherapy decisions in early-stage breast cancer. The MINDACT trial included almost 7,000 patients (over 800 from Germany), across 112 institutions in nine different European countries.